Polymer compositions with improved retention of properties under mechanical and thermal stresses
The invention provides a composition comprising the following: A) an ethylene/α-olefin/diene interpolymer; B) an ethylene/α-olefin copolymer with a Mooney Viscosity [ML(1+4) at 125° C.] greater than 40; and C) a peroxide; and wherein the α-olefin of the ethylene/α-olefin copolymer of component B comprises at least four carbon atoms; and wherein component A is present in an amount from 50 to 95 weight percent, based on the sum weight of components A and B.
1. A composition comprising the following:
A) an ethylene/α-olefin/diene interpolymer;
B) an ethylene/α-olefin copolymer with a Mooney Viscosity [ML(1+4) at 125° C.] greater than 40; and
C) a peroxide; and
wherein the α-olefin of the ethylene/α-olefin copolymer of component B comprises at least four carbon atoms; and
wherein component A is present in an amount from 60 to 95 weight percent, based on the sum weight of components A and B; and
wherein components A and B comprise at least 80 weight percent, of the composition, based on the weight of all the polymer components of the composition.
2. The composition of claim 1 , wherein the ethylene/α-olefin copolymer of component B has a percent crystallinity less than 20, as measured by DSC.
3. The composition of claim 1 , wherein the ethylene/α-olefin/diene interpolymer of component A has a percent crystallinity less than 20, as measured by DSC.
4. The composition of claim 1 , wherein the ethylene/α-olefin copolymer of component B is a homogeneously branched linear ethylene/α-olefin copolymer or a homogeneously branched substantially linear ethylene/α-olefin copolymer.
5. The composition of claim 1 , wherein the ethylene/α-olefin copolymer of component B has a Processing Rheology Ratio (PRR) value greater than, or equal to, 4.0.
6. The composition of claim 1 , wherein the ethylene/α-olefin/diene interpolymer of component A is an EPDM.
7. The composition of claim 1 , further comprising at least one additive.
8. A crosslinked composition formed from the composition of claim 1 .
9. An article comprising at least one component formed from the composition of claim 1 .
10. The article of claim 9 , wherein the article is an automotive part.
11. The article of claim 9 , wherein the article is an engine component.
12. The article of claim 9 , wherein the article is a hose.
13. The composition of claim 1 , wherein the ethylene/α-olefin/diene interpolymer of component A has a Mooney Viscosity ML(1+4) at 125° C., greater than, or equal to 70.
14. The composition of claim 1 , wherein the ethylene/α-olefin/diene interpolymer of component A has a Mooney Viscosity ML(1+4) at 125° C., greater than, or equal to 80.